

where \(M_k, N_k\)  are the proximal matrices satisfying [1]}, [2]}
\(0< \gamma _{-} I \le M_k \le \gamma _{+} I, \quad 0< \mu _{-} I \le N_k \le \mu _{+} I, \quad 0<\gamma _{-}, \ \mu _{-}<\gamma _{+}, \ \mu _{+} < +\infty .\) 
